MYC/BCL6 double-hit lymphoma (DHL): a tumour associated with an aggressive clinical course and poor prognosis.

AIMS: Large B cell lymphomas with MYC and BCL6/3q27 rearrangements, designated MYC/BCL6 DHL, are uncommon. Our aim was to better characterize this group of tumours.

METHODS AND RESULTS: We studied the clinicopathological features and outcome of 13 patients with MYC/BCL6 DHL and compared this group to a group of 83 MYC/BCL2 DHL patients. There were eight men and five women, with a median age of 63 years. Eleven tumours were classified as diffuse large B cell lymphomas (DLBCL) and two were B cell lymphoma, unclassifiable, with features intermediate between DLBCL and Burkitt lymphoma (BCLU). Immunohistochemical analysis showed that these tumours were positive for BCL6 (100%), BCL2 (eight of 10; 80%) and CD10 (eight of 10; 80%). Nine of 12 (75%) cases had a germinal centre B cell (GCB) immunophenotype; in one case data were incomplete. All patients were treated with chemotherapy. The clinicopathological features of MYC/BCL6 DHL were similar to MYC/BCL2 DHL, except that MYC/BCL6 DHL had a GCB immunophenotype less often. Patients with MYC/BCL6 DHL had a poor overall survival, similar to patients with MYC/BCL2 DHL (P = 0.32).

CONCLUSIONS: MYC/BCL6 DHL is an aggressive B cell lymphoma and patients often have an aggressive clinical course and poor prognosis, similar to patients with MYC/BCL2 DHL.